The study evaluated the safety and efficacy of the progesterone-primed ovarian stimulation (PPOS) coupled with gonadotropin (FSH) for infertile women with polycystic ovary syndrome (PCOS) who were assigned for ICSI and frozen blastocyst transfer.

200 infertile women were divided randomly into Group C, which received Cetrorelix injection (0.25 mg daily) on day-6, and Group S, which received oral dydrogesterone (20 mg/day) on day-2 of the menstrual cycle till the trigger day. All patients received an FSH injection of 225 IU daily from day-2 till triggering day. ICSI was performed and day-5 blastocysts underwent vitrification ultra-rapid cryopreservation till being transferred. Outcomes included the ability of PPOS to suppress the premature luteinizing hormone (LH) surge and prevent the development of ovarian hyperstimulation syndrome (OHSS), the incidence of profound LH suppression, the number of retrieved M2 oocyte and fertilization, chemical and clinical pregnancy rates, and the miscarriage rate.

Inclusion Criteria:

• Infertile PCOS women;
• aged 20-35 years;
• had BMI <35 kg/m2.

Exclusion Criteria:

• Women who were younger than 20 or older than 35 years,
• obese of grade II or III,
• had poor OR, other causes of infertility,
• had previous attempts of IVF, had a history of repeated pregnancy loss.